Automatic telephone system



AUTOMATIC TELEPHONE SYSTEM Filed Nov. l5, 1925 imp@ 125% .To afl i/,fiiogw il, wwf/f (mi Be .13 known #iwf L L# w citizen Uf ih@ Ume fzges'f siding at Evanstom im the cog V' u' @of 5 and Siate of uos, hum invented 'i' new und useful, mpm'veiiueus in m'on' "his, Telephone Sysems, Uff Whisk the 'oowmg is a ful, den l concis@ and @Kimi fescrp- .mL

This ilu/'elution 'laefs 'to mlbon'lac tell@ phone emmngs and. more particularly it@ a trunk 3:1 untng' Switch 'fm' us@ in such Sjfstems.

its object is to pro viavia an mp o It is thought that n'mntm w'i ha most readlly 'unerstmd from :a desnmpi'm@ of the operation of *the s'vsm'r.

The Calling' subsm'm Sja'bfsts; tiates a Callby remoafnp; his Fem closing be line crcu; which camas ne im@ switch LS to plum@ and seize a ir' secor. This selec'im.' :m succeeing selecmf 5G than set in the Wmown mammie 'im min 11min HJC: dimi brush 18Abridges its terminals. The escape` -magnet 9 is slow to operate and will not kactuate its armature by the momentary llow4 1 lof current it may geirbelore Vtest? relay 17 operates `Relay 17 isdesigned to bey fast to v"operate and to release. As soonl as airidle f 'trunk is found, the absence of ground on its' test terminal' 22 causes the test relay-17 to .20 release, and its Varmaturey 'then 4applies ground-,to thefcss'pc magnet 9 for a'sul- .cient period to' ,energize the qsame. The

Y escape kmagnet-is constructed and arranged.

to move its arms4trom position 2 to ition Supon energiaation. 1n vthis position, arms 24 and 25 v`entend the v'calling/.yline through toithaalled line terminals. Clir-v rent ,is supplied ,tothe calledl line ltransmitter ythrough impedance coilf 42;' Condensers "39 4f)V 4lsepnia/tethe calling and called current "the well-knownvmanner. ,Side switch arm 15in position 3 applies a direct ground tothe 'multiple test-terminals 220i the seized lline. The ringing 'circuits are not i335 shown'since they form no part of the invention andmay be of'any A)voll-known t Assume, howeyer. that the digit dia ed is two' insieadof one. It will be remembered that brush 11 was advanced to the test ter minal 15 when 4the line was again closed by the dial D, that relay 1 remained operated preventing the relay 7 from reoperating, and

A that in consequence, relay 8 andthe escape magnet 9 released. If, however, another impulseis produced at the dial l), the line cir- @uit is again opened, relay 1 releases and relay 7 again operates, thereby preventing .relay 8 and consequently the escape, magnet 9 from releasing. W ilie reoperation of relay 7 connects ground to terminal 15, thus closing the circuit to reoperate the stepping magnet 32, T'thereby advancing brush -11 to terminal 27 and ,brush 18 to terminal 20. It should be .55 observedthat until this second impulse is produced bythe' dial D, the stepping ma i net 32 could not operate to advance t e i, Ab1nshes'48, 47, 11 and 18, unless the trunk `'l'i"liunting".movemerit was initiated by the rew lease ofthe slow relay 8 and the escape magv vlnetl). With brush 11 resting on terminalA 27, the circuit for the stepping magnet is opened awaitingthe release of relay 7 hence n the brushesi, 47, 11 and 18 cannot advance. "r lli/'hen the luie is again closed at the dial D,

relay 1 reoperates and relay 7 releases. The. release of relay 7 "connects ground to the test terminals 27, 23, and 28 -of the remaining trunks in the first trunk grou and'the stoppin magnet now operates an advancesl the brus es from one set of terminals to another until brush 11 is resting upon the test terminal 29 when the circuitthrough the Steppin magnet is opened. Brush 11, according y, remains lat rest upon test termi-` nal 29 associated with the first trunk in the second grou u The dial is designdso thatthe period of time durin which the im ulse springs of the dial are c osed between reaks is Sullicient to permit the stepping magnet 32 to function and advance the brushes 48, 47, 11, and 18 from the terminals of thesecond line in a articular group to the terminal of the first e inthe next succeeding grou before, by the release of. the impulse re a 1 upon the succeeding break of the dial impulse springs, relay 7 reoperates to close the operating circuit for the ste ping magnet 32 to further advance the bru es 48, 47, etc. elay 8 is designed to be slow to release so that it remains operated during the period that its operating circuit is open, namel from the advance of the brush 11 from the first terminal (11, 15, 29, etc.) of a group until the reoperat-ion of relay 7 on the next succeeding impulse produced by the When advancing, brush 11 bridges adjacent terminals, but when jcentered it is in contact with only one of the terminals 10, 14, l5, etc.

After the last impulse'in the train of impulses hasrbeen sent, in this case after the second impulse, the prolonged closure of the line by maintaining relay 1 operated, prevents relay 7 from reoperating; hence slow relay 8 now releases, permitting the escape magnet 9 to advance the side switch-arms 24, 25, 12, 16, 21, etc., to position 2,5 in which position the trunk hunting movement of the connector is initiated'.

In case all the trunks in the desired group are busy the switch will continue ,to step from grounds on the busy test multiples as 1 15 described and will com'e to rest due to the test brush 18 reaching a non-multipled or dead terminal 43, one owhich follows each group. Due yto brushes47 and 48`resting on a corresponding pair of terminals 44, 45, to which a ybusy tone source 46 is permanently connected and due to side switch arms passing to position 3 when test brush 18 moved onto dead terminal 43, busy tone is applied to the calling line to notify the calling party that all the trunks are busy.

Release is effected bythe replacement of the receiver by the calling party which, by opening the circuit at the connector releases relay 1, thereby releasing slow relay imacat 2. -This relay at its left armature, and the withdraws the holding pawls, and a resten' ingspring (notshown) restores the selector to its normal positions The side switchis restored by a mechanical connection between its arms and the release magnet armature in the well-known manner.

if the calling subscriber abandons the v'call before an idle trunk is selected the release of the impulse relay l and relay t?, operates the release magnet over an obvious circuit.

llt should be understood that the number-` of trunks or lines in a group is not fixed but may be varied at will, some groups contain` ing but few trunks or linesgand other groups containing a larger numbenI It is also evi-` dem; that the trunks are designated by their group number and not by individual trunk numbers, ,or expressed in anotherway, it may be consideredfthatthersttrunk in each group is designated .by a distinguishing number, and that the' en iaining trunks in.

That is elaimed'i y 1. An automatic. switch' responsive toim pulses, ncounorising,r sets 'fof 'terminals arranged in groups. ,andrv 'brushes capable of passing over said terminals, means respon each rroup are unnumbeited lines.

sive to an impulse loi.; initiating the advance of the switch Abrushes preparatory to seizing the irshset of 'termina s in. a group, and means eiective between impulses oit the same impulse train for .continuing ,to advance the switch brushes to the first set ci' terminals ic switch, responsive to impulses, having a group hunting movement, comprising ci trunk terminals arranged in groups, hru'les capable of hunting over said terminals means responsive to an impulse for initie. ing; the group hunting movement oil 'the sw' brushes, mea-ns effective between impuls .for advancing* the switch brushes to the set oi 'trunl uminals in the first trunlfgroup, and meansiesponsive to another impulseoit the same impulse train for 'passing over all the of trunk terminals in the lirst trunk `group and -for continuinp,Y the group huntingr movements An automatic switch, responsive to impulses, havinge' a ejroup huntingr movement, comprising sets of trunk terminals arranged in, Igroups, brushes capable oi hunting'over said trunk terminals, means responsive to an 4 impulse for initiating' the group hunting 4:. In a telephone system, a progressively movable selecting switch having both a grouphuntmg and a trunk hunting move-` ment, an .impulse sender, a circuit including' the switch and sender, means controlled by the impulse sender for initiatingr the group hunting movement ot said switch, means for continuingsaid movement after the last impulse of a train ot impulses has been transmitted -by the impulse sender, and means effective thereafter for initting; the trunk. hunting movement of the switch.

5. In a telephonesystem, a selector switch having both a group hunting' and a trunk hunting movement with access in one level to successive groups of' trunks, an impulse sender, a circuit includingr said switch and sender,` means responsive to a train of iin-- pulses produced by the impulse sender for initiating the group hunting movement of said switch, means for continuingy said move ment irrespective ol the busy Lor idle eondition 0i. the trunks passed over until after the last impulse of the train oit impulses has been transmitted, and means etlective thereafter for initiating thetrunl: huntingl movement of the switch. i

6. ln a telephone system, an'impulse re lay, 'an automatic switch controlled thereby having` trunk groups, a relay connected to a back contact ofthe impulse relay and opranged Yto start said switch on an auton'iatie' huntingmovement upon the movement of the armature oil" said'magnet in one direction and means to continue the advance of said switch upon the movement ott-hc arma-` ture in the other direction.

8. ln a telephone system., :in automatic switch havingtrunk terminals arranged in `ejroups, the zxroluis all arranged in a single row, a circuit includifiun a calling' line an iu'ipulse sender and the impulse relay of' sai d automatic switch, `means 'tor starting' said automatic switch in nlotion as soon as the senderbegins to interrupt said circuit. means including" a Contact oli" the impulse relay and terminals of said automatic switch for designating the group of trunks in which the automatic switch is to commence hunting, and means including multiple test tern'ilnas of the said group for coritrollinu` further movement ot the autoimitic switch..

9. ln a telephone system, a single motion connector having groups of multiple trunk terminals and a row of multiple testl terminals, trunk lines connected' thlcreto, a telephone line, an impulse sender thereat, a cir-` cuit including said line, said sender and the impulse relay of the connector, means associated with said connector and constructed and arranged to advance said connector onto the first trunk of the first group on the lirst terminals in a single row, a row of non- .apportioned to the next tru multipled terminals in said connector, a row of multi le test terminals, a circuit including a ea ing line an impulse sender and the impulse relay of said connector, a circuit inclu a contact closed by the lirst release of the 1m ulse relay armature, the first terin t e row of non-multipled terminals and a brush of the connector for stepping the connector 'oil the lirstterminal, a circuit including a contact lclosed by the next attraction of the impulse relay armature, the second terminal in the row of non-multipled Vterminals and said brush for stepping the connector. onto the' lirst trunk in the first u a circuit includin a contact closed y t e next release of t e impulse relay armature, the third of said non-multipled terminals and said brush for stelpping the connector oli the said first trun circuits includingla contact closed by the next attrac- -tion of t l l non-multi led terminalsof the rst trunk group an said brush for stepping the connector to the lirst non-multi led terminal group, and circuits for continuing the movement of the connector and de endent upon the busy coriselected movement of said sw1tch,"mcans dition of the mu tipled test terminals ofthe up. v

11. In a telpehone system, a selector switch having both a group hunting and a trunk hunting movement with access in one level to consecutively numbered groups of trunks, a calling line equipped with, an impulse Sender having acce to the trunks via the switch, a circuit including` said switch and inlse sender, means responsive to an imp for initiating the hunting or continuing said movement between im ulsee. irrespective of the busy or idle condition of the -trunks in the groups passed over u ntil after the last im ulse of an impulse train has been transmitte when the switch will be set upon the first trunk of theV selected group, means ell-ective thereafter for initiating the trunk sive to an impu e impulse relay armature, all thenauseas hunting movement of the switch, and means effective if all trunks in the selected trunk group are busyjor indicatin the busy con dition thereof to the calling ine. z

12. An automatic switch, vset responsive to` impulses, having both a. group hunting and a trunk huntin movement, means response -for Ainitiating the group hunting movement, means ei'ective between impulses for continuing the group hunting movement, the group selected depending upon the number of impulses transmitted, and means for be 4'inning the trunk hunting movement after t e proper group has been selected.

13. An automaticswitch, set responsive to impulses, having a `group hunting movement fol owed by a Itrunk hunting movement, means responsive to an impulse for initiating the group hunting movement, and means ell'ective between impulses for continuing .the group hunting movement, the group selected depending upon the number o impulses transmitted.

14. An automatic switch, set responsive to imlpulses, having a grou hunting movement fo owed by a trunk unting movement, means responsive to anfimpulse for initiatin the group hunting movement, and means e ective between impulses 'for continuing the group hunting movement, the group selected varying in accordance with the number of impulses transmitted.

15. In a telephone system, atraveling switch controlled by impulses, and means changeable at lwill for varying the extent ofthe switch movement per impulse.

16. IIn a telpehone system, a connector switch, consecutively numbered ups of subscribers lines connected to said switch, said groups being serially arra and v ariable in size, and means ope le to select any desired group and to seize the first idle line therein.

17. In a telephfone system, a single motion connector switch, cpnsbcutively numbered groups of subscribers lines connected to said'switch, said groups-being serially arranged and .variable in. size, and means operable to select any desired group and to seize the first idle line therein.

18. In a telephone system, aselector switch, consecutively numbered and serially arranged groups of lines connected to said switch, each of unnumbe lines an a single numbe line, means operable to select a numbered line, and means effective' thereafter to seize the first idle line 'inthe up selected.

In witness whereof, my name this 10th day of November, A.. D.

up com rising a pluralit Illiereunto subscribe T 

